Antenna base



FIG. 1 is a left elevational view of an antenna base showing our new design;

FIG. 2 is a front elevational view thereof;

FIG. 3 is a right elevational view thereof;

FIG. 4 is a bottom plan view thereof;

FIG. 5 is a top plan view thereof;

FIG. 6 is a rear elevational view thereof;

FIG. 7 is a perspective view thereof; and,

FIG. 8 is a perspective view thereof.

The broken lines in the drawings represent unclaimed portions of the design, which form no part of the claim. 

CLAIM The ornamental design for an antenna base, as shown and described. 